Multiple-jet exhauster



C. A. DUNHAM MULTIPLE JET EXHAUSTER Jan. 3l, 1928.

eet l 2 Sheets-Sh Filed Dec.

6% mm mw Jan. 31, 1928.

c. A. DUNHAM MULTIPLE JET EIXHAUSTEIR Filed Dec. 26, 1925 2 Sheets-Sheet 2 Patented Jan. 3l, 1928.

1,657,665, PATENTy OFFICE.

CLAYTON A. DUNHAM, OF GLENCOE, ILLINOIS, ASSIGNOR TO YOUNG PUMP COMPANY, l' CHICAGO, ILLINOIS, A CORPORATION 0F INDIANA.

MULTIPLE-J ET EXHAUSTEB.

Application filed December 26, 1925. Serial No. 77,895.

. This invention relates to an improved multiple yjet. exhauster, especially adapted for use in heating systems.

In some heating systems, a continuously circulating liquid stream, or hurling circuit, is employed, Which is drawn from a receiving tank and forced through a vacuumroducing chamber inthe form of a jet, tie liquid stream then being returned m to the tank. Return fluids from the heating system are drawn into the vacuum chamber by the reduced pressure, and entrained by the liquid stream and carried into the receiving tank.

The present invention relates to an improved form of jet exhauster for use in such a system, and comprises means for projecting a plurality of separate jets into and through the vacuum chamber, the jets cooperating with one another to more etii rciently Withdraw and collect the return fluids from the heating system.

The general object of this invention is to increase the efficiency of jet exhausters, using liquid for the actuating fluid, that is, to reduce the quantityv of actuating liquid required perA unit of fluid mixture exhausted and to permit operation with the actuating liquid at high temperatures as well as at low, and the reduction of the power consumption required to furnish the liquid at the pressure required for actuating the'jet. In this improved exhauster, the stream of actuatingliquid supplying the jet is broken up into a number of streams and each stream into small particles during its passage across the suction space, thereby providing for entrainment of the Huid' being exhausted with the actuating liquid so that the actuating liquid serves as a multiplicity of small pistons, While preserving the contractive action of the jet when the liquid is at atmospheric or approximately atmospheric temperatures. This provides a maximum actuating liquid surface passing through the suction area per unit of time, but with the use of a minimum volume of actuating liquid. i i

Another object of the invention is to control the expansive action of the actuating liquid, when hot, Within the nozzle from which the jet is discharged, so as to permit conversion of a portion of the heat energy into kinetic energyl applied to the liquid particles, as a result of the expansive action.

are attained by the use actuating nozzles, and shaping the liquid passages in The above objects of amultiplicity of by properly these nozzles.

Other objects and advantages of the invention Will be more apparent from the following detailed description of certain approved a paratus designed for `putting into eti'ect tie principles ofthe invention.

In the accompanying drawings:

Fig. 1 is a side elevation of that portion of a heating .system in which the exhauster is used.

Fig. 2 is an end view ,j `of the apparatus shown in Fig. 1, the pump-operating motor being omitted.

Fig. 3 is a side View of the completeexhauster, showing the inlet and outlet connections.

Fig. 4 is a central longitudinal section through the exhauster, taken substantially on the line 4-4 of Fig. 5. j

Fig. 5 is a transverse section, taken substantially on line 5-5 of Fig. 3.

Fig. 6 is a transverse section, taken substantially on the line 6-6 of Fig. 3.

j Fig. 7 is a longitudinal central section on an enlarged scale, through one of thel im- 'proved nozzle and delivery-tube units.

Referring first to Figs. 1 and 2, We will brieiydescribe a typical heating system in which this improved exhauster may be used. The receiving tank 1 is adaptedto hold a quantity of Water, or actuating liquid, which is Withdrawn near the bottom of the tank, through` pipe connection 2 `by a pump 3 driven by the electric motor suitable driving means. The liquid is forced by pump 3 through the pipe 5 and inlet connection 6 to the vacuum chamber 7, through which chamber the liquid is discharged under pressure as a jet, or plurality of jets, which are received in the outlet connection 8 and pass back into the upper end of tank 1. This continuous, forced circulation of Water from and back to the tank 1, through the excmY 4 or any other hauster 7, is known as the hurling circuit. v

The return fiuids from the heatingsystem are conducted through pipe 9, check-valve 9', and a strainer 10 into the vacuum chamber 7 through inlet opening 11 (see Figs. 4 and 5). These return fluids are entrained by the liquid jets, as described more in detail here` inafter, and are carried through pipe connection 8 into the receiving tank l. A liquid tankl. Obviously,

now about to be described, is capable of use discharge pipe 12, leading `from the inlet connection 6, is controlled by a valve 13, which is normally closed so that all of the liquid-Withdrawn from tank 1 by pump 3 will be forced through the hurling circuit. A suitable valve is provided in `the upper portion of tank 1 to discharge the gases returned from the heating system, but the returned liquid will gradually augment the supply in tank 1 until the rising water level in the tanky raises the float 14 (sec dotted lines, Fig; 2,) and through the link and lever connections 15 yopen the valve 18 to permit the discharge of liquid throughthe pipe 1Q. W'henthe liquid supply in tank 1 has been suilieiently diminished, thelloat 1e Willsinl: Vagain closetlie outlet valve 1.3. Sysy tems of the typel just. briefly described ,are

well knownpthe particular object of y.the

present invention being to provide animrovedexhauster, positioned in the casing or more eliciently accomplishing the withdrawalof the return fluids into the receiving the improved cxhauster for other purposes, and in other systems than thathereshoivn, which has been described merely by way of example.

The casing member 7,y enclosing the socalled vacuum chambei, has a flanged extension 16 at one side adapted to connect with the. 1 strainer 10, the returned fluids flowing intonthe vacuum chamber through passage 11. The ends of the .casingi'Y are in the form of flat flanged plates 17 and 18, having respectively a plurality of inlet and outlet openings 19 and 20 in alignment with one another.` The li uid inlet connection 6 is; ianged Vat one end .a1 to connect with the pump Outlet, and Vis flanged at the'other end 22 to 'connect with the end )late 17 of casing 7.. End. Plate 22 is provideil with a-plurality of discharge openings adapted to align iaith the openings 19 in the end of casing? to form continuous passagesfirom the inlet connection G to the chamber in casing 7. Each nozzle '24 has an exterior annular iiange 25 at its inlet end adapted` to iit an enlargement in inlet opening 19,l the nozzles being clamped in place by the end plate 22 o inlet connection 6. This is a convenient means` for anchoring the nozzles in place in the easing 7., but other means, such as a screw threaded connection might be used. `The outlet or discharge connection 8 is flanged at one end 2G to connect with the end plate 18 of casing il, the end 2G beingfprovided with a plurality of openings 27 adaptcryl to 'alignwith the oassages 2O in endplatel 18. `he delivery tu es 28 have outer Menges or collars 29 adapted to tit enlarged portions of the openings 20, whereby the delivery tubes will beclamped securely in place against endvvise' movement when the end plates 18 andQG are assembled 'and secured together.

" 7. each nozzle 24 In the construction here shown, the other end of outlet connection 8 is turned at right angles, as at 30, and hanged, as at 31, to connect uith the upper end ot tank l.` Of course, this portion of the device may be varied to suit the installation in which the exhauster isused.

Referring now more particularly to Fig. encloses a fluid passage, the inlet portion 32 of' which is cylindrical and of suilicientsizc to make the pressure loss negligible in this portion of the nozzle. At 33 the'diameter of the passage `is gradually diminished until it reaches its minimum at the restricted throat 81,. the passage then flaring at 35 out to the somewhat enlarged discharge opening 3G. The `flare between throat 3l and the delivery or discharge opening 361s proportioned according to the expansive action desired which in turn is governed by the temperature of the actuating liquid, the degree of expansion desired, and the physical properties of the actuating liquid. Since the water in tank 1 is derived from condensed steam, it will have a. rather high temperature, and this temperature may even be above the boiling point at the rcduced pressure existing m the exhausting chamber into which the jets discharge. The flared portion 35 of the improved discharge nozzle permits the liquid to expand or partially v-aaorizc, and lower its tempt-rature, the heat eing transferred into kinetic cnergy andutilized in the exhausting process. Any considerable vaporization of the actuating fluid thus avoided,` and at the same time the elicicney of the jet is increased. lVhen the usual converging nozzle is used a scattering or flaring of the jet is caused by the increased internal pressure, and the de creased `external pressure vwhen the jet emerges into the low pressure exhausting chaniber. This avoided by the expanded or diverging nozzle 55, which materially decreases `the internal pressure ol thejet. The added kinetic encrg derived from the heat released by this preliminary Vexpansion of the jet serves to project thc-water partcles acrossl the expanding chamber with con siderable force in a substantially straight stream, which will be entirely received with` in the delivery tube 23S.`

The delivery tube 28 has a flared inlet opening 37 which diminishes` in diameter toward the cylindrical passage 3'.` This passage 38 is graduallyincreased in dialin eter or flared out, at 39, until. it reaches the outlet f1() where the liquid is dischargedinto the outlet pipe 8.`

vIn operation, the liquid is forced under.` pressure by pump 3', intothe inlet passage 32 of nozzle 24, and thence through the restricted throat 3a, which projects thel liquid in the form of a jet under high 4velocity through'the 'intervening yspace in the lllll Cal Laureati vacuum chamber toward the deliveryv tube 28. The flared dischargev opening 35 be` ond the throat 34 of the nozzle permits the iquid to expand so that the heat released asa result of the pressure change within this portion of the nozzle is utilized to increase the kinetic energy of the water particles in the jet and reduce the temperature of the water. The jet will be projected straight across the suction space in the form of a multiplicity of small liquid particles, which entrain port-ions of the :returned fluids in the chamber 7 to carry these fluids with the liquid stream into the open end 37 of the deliveryl tube 28. The bell-mouthed '4 or flared entrance opening 37 of the delivery tube is to insure proper guidance of the jet ofactuating liquid into the tube, and also provide increased area for the reception of the fluids which are being exhausted from the chamber 7.` Thecombined fluids passI through Lthe passage 38 in tube 28 into the delivery pipe 8, the flared end 39 of the delivery tube serving to convert the kinetic energy of the stream into pressure energy, facilitating the passage of the fluids through pipe 8. j

In any liquid jet exhauster of this general type, when the `actuating liquid stream passes across the space intervening between the nozzle and the delivery tube, the fluids in the chamber of which this space is a part, will be withdrawn and taken away bythe actuatingfluid as a result of 4(l) the contraction of the jet, (2) the friction of the actuating liquid with the fluid contents of the chamber, and (3) by entrainment of the fluids being exhausted with the particles of the actuating liquid stream. The removal of the fluids from the chamber will reduce the pressure therein and causemore of" these return fluids to flow into the chamber `7 through pipe 9 and strainer 10. Byusing a plurality of nozzles, thus providing a plurality of smaller` `actuating jets'instead of one larger jet, the maximum actuating liquid surface passing through the suction area per unit of time, is providedwith the use of a minimum volume of the actuating liquid. Thus a. largely increased friction vsurface is presented to the fluids being exhausted. The smaller'stream of the jet, to-

gether with the peculiar conformation of the projecting nozzletends to break up the actuating liquid into a multiplicity of small particles during its passage across the suction space, thereby increasing the entrainment of the fluids being exhausted between these liquid particles which serve as small pistons. This does not interfere withthe contractive action of the jet when the liquid is at atmospheric or approximately atmos-` pheric temperatures.

Owing to the heat loss by radiation from tank l, the water in the hurling circuit,

which is projected through the nozzles, will ordinarily be at a lower temperature than the fluids returned from the heating system through pipe 9. Part of these returned fluids are usually in the form of vapor, and the colder water in the jets will have a condensing action on this vapor, thus aiding the production of a vacuum in chamber 7. This exchange of heat from the vapors to the liquid of the jets is facilitated by the greatly increased contacting area of the two fluids resulting from `the use of a plurality of small .jets instead of onelarger jet.

Thesev small nozzles may be made of 'a standard and mostleflicient size, and the size or capacity of the exhauster can be varied as desired by simplyfusing-a larger or smaller vacuum or exhausting chamber, and' increasing or diminishing the number of nozzles used therein.Vv In the example illustrated, six nozzles are used, but this number could be increased or diminished as desired 4without materially affecting the principles of operation of the exhauster. Although `it is preferableto use a separate deliverytube 28 for each nozzle 24,7as inthe apparatus illustrated and described above, all of the nozzles might proj ect their jets into a single delivery tube. j

I claim: Y i

l( A liquid actuated jet exhauster comprising a casing enclosing an exhausting chamber, the chamber having an inlet opening in one side for fluids, and having aligned` inlet and outlet openings in its opposite ends, a connection for delivering liquid to the exhausting chamber, saidconnection having a lplurality i ofv openings in its delivery end adapted to,` mate with the inlet openings in the casing, another connection for carrying c away the liquid dischargedfrom the outletnpenings in the other end of the casings, "saidnlatter `connection having a plurality1V of openingsin'V its receiving end adapted to mate with the outlet openings in ther chamber, a plurality of nozzles mounted in the inlet openings and a plurality of delivery tubes mounted in the outlet openings, whereby the liquid is projected across the exhausting chamber in a plurality of separate jets, each nozzle and delivery tube having an outstanding collar which is clamped between the abutting end walls of the casing and the inlet or outlet connection` 2. The method of withdrawing fluids from an exhausting chamber consisting in circulating a stream of liquid and projecting it as a jet through the chamber, the initial vtemperature of the liquid stream being Ihigher than the boiling point of the liquid at the pressure prevailing in the chamber,

and expanding the stream before the jet is formed to reduce the temperature of the liquid below this boiling point.

3. The method of withdrawing luids from an exhausting chamber consisting in circulating a stream ot liquid and projecting it as aplurality of small jets i through the chamber, the initial temperature of the liqnid stream being higher than the boiling point of the liquid at the pressure prevailing in the chamber, and expanding the jets .at their formation so as to reduce the temperature. of the liquid below this boiling point.

4. .In `aV vacuum pump system, .in combina tion, a tank, a pipe circuit including a jet exhauster, means for forcing heated liquid from ,said tank through the circuit and back to the tan-k, and means for delivering fluids to said exluuister,N the exhanster embodying means for dividing theliquid stream into a plurality ofseparate jets and tor expanding each jet prior to its discharge through the exhauster. j i

5; In -avacuum rpump system, in combination, a tank, a pipewcircuit including a jet exhauster., means forifoi'cmg heated liquid from said tank through the clrcuit and back to the tank, and means for' deliverin iuds to said exhauster, the exhauster embed plurality of nozzles for projecting the liquid stream through the exhauster as a plurality of separate jets each nozzle having a ilared discharge opening'for permitting the liquid to expand prior toits discharge. y j

6. lnfa vacuum pump system, in combination, a tank, a pipe circuitincluding a jet exhauster, means for forcineyjheated liquid from said tank through `t e circuit and back to the tank, meansy for delivering itluids to said exhauster, the exhauster embodying a nozzle for projecting the liquid `stream through the exhanster in the form ot a jet, the nozzle havinpr `a flared discharge opening ,for permitting the liquid to expand prior to its discharge', i

- 7. In a vacuum pump system,

ying a e in combination, a tanlga jet yerhauster, means for withdrawin liquid from the lower portion of the ta y andutorcing it up through the jet exhaustcr, and connections for delivering the liquid andexhansted'gases from the upper portion of the exhauster to the upper portion of the tank, Athe exhauster embodying means for dividing the liquid stream into a plurality of separate jets and for expanding each jet prior to its discharge through the exhauster to reduce its temperature. 8.7111 a vacuum pump system, in combination, atank, a jet exhauster., means for withdrawing liquid from the lower portion of the tank andforcing it up through the jot exhaiister1 and connections for delivering the liquid and exhausted gases from the upper portion of the .exhauster to the upper portion of the tank, the cxhauster embo ing a plurality of nozzles for :projecting t c liquid upwardly through the exhauster in the'form of a. plurality of separate jets and for expanding each jet prior to its discharge through the exhauster to reduce its temperature.

o 9. In a vacuum pump system, in combination a tank, a pipe circuit includinnr a jet exhauster, means for forcing heated: liquid from said tank through the circuit and Iback to the tank, and meansor delivering fluids to said exhauster., the exhauster embodying an exhausting chamber, means'for projecting avjet through the chamber, and means for expanding the jet to reduce its temperature prior to its discharge through the chamber.

10i The method of. withdrawing fluids from an exhausting chamber consisting in circulating a stream of highly heated liquid and projecting it as a jet through the chamber, and expanding the liquid stream before the jet is 'formed to reduce its temperature so that it will not vaporize while passing through the pressure exhausting chamber. 

